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991.
992.
Reza Shabanian Abdolrazagh Kiani Elaheh Malakan Rad Hosein Eslamiyeh 《Pediatric cardiology》2010,31(2):274-276
This report describes a 3-month-old boy with isolated left ventricular noncompaction admitted to a medical facility due to heart failure and dysrhythmia. His electrocardiogram showed a short PR interval and a normal QRS complex after abortion of supraventricular tachycardia in favor of Lown-Ganong-Levine syndrome or enhanced atrioventricular nodal conduction. 相似文献
993.
Reza Monfaredi Iulian Iordachita Emmanuel Wilson Raymond Sze Karun Sharma Axel Krieger Stanley Fricke Kevin Cleary 《International journal of computer assisted radiology and surgery》2018,13(11):1829-1841
Purpose
This paper presents new quantitative data on a signal-to-noise ratio (SNR) study, distortion study, and targeting accuracy phantom study for our patient-mounted robot (called Arthrobot). Arthrobot was developed as an MRI-guided needle placement device for diagnostic and interventional procedures such as arthrography.Methods
We present the robot design and inverse kinematics. Quantitative assessment results for SNR and distortion study are also reported. A respiratory motion study was conducted to evaluate the shoulder mounting method. A phantom study was conducted to investigate end-to-end targeting accuracy. Combined error considering targeting accuracy, respiratory motion, and structure deformation is also reported.Results
The SNR study showed that the SNR changes only 2% when the unpowered robot was placed on top of a standard water phantom. The distortion study showed that the maximum distortion from the ground truth was 2.57%. The average error associated with respiratory motion was 1.32 mm with standard deviation of 1.38 mm. Results of gel phantom targeting studies indicate average needle placement error of 1.64 mm, with a standard deviation of 0.90 mm.Conclusions
Noise and distortion of the MR images were not significant, and image quality in the presence of the robot was satisfactory for MRI-guided targeting. Combined average total error, adding mounting stability errors and structure deformation errors to targeting error, is estimated to be 3.4 mm with a standard deviation of 1.65 mm. In clinical practice, needle placement accuracy under 5 mm is considered sufficient for successful joint injection during shoulder arthrography. Therefore, for the intended clinical procedure, these results indicate that Arthrobot has sufficient positioning accuracy.994.
Zargar M Kalantar Motamedi SM Karbakhsh M Ghodsi SM Rahimi-Movaghar V Panahi F Saadat S Khaji A Davachi SM Ganji S Khodabandeh M Abdollahi Far S Abdollahi M Zarei MR 《中华创伤杂志(英文版)》2011,14(3):131-136
Objective
The high burden of injuries in Iran necessitates the establishment of a comprehensive trauma care system. The purpose of this paper is to describe the current status of trauma system regarding the components and function.Methods
The current status of trauma system in all components of a trauma system was described through expert panels and semi-structured interviews with trauma specialists and policy makers.Results
Currently, various organizations are involved in prevention, management and rehabilitation of injuries, but an integrative system approach to trauma is rather deficient. There has been ongoing progress in areas of public education through media, traffic regulation reinforcement, hospital care and prehospital services. Meanwhile, there are gaps regarding financing, legislations and education of high risk groups. The issues on education and training standards of the front line medical team and continuing education and evaluation are yet to be addressed. Trauma registry has been piloted in some provinces, but as it needs the well-developed infrastructure (regarding staff, maintenance, financial resources), it is not yet established in our system of trauma care.Conclusions
It seems that one of the problems with trauma care in Iran is lack of coordination among trauma system organizations. Although the clinical management of trauma patients has improved in our country in the recent decade, decreasing the burden of injuries necessitates an organized approach to prevention and management of trauma in the context of a trauma system. 相似文献995.
996.
Background: Cystic fibrosis is a monogenic recessive disorder found predominantly in Caucasian population. This disease arises from mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. In this study we consider poly T polymorphism c.1210-12T[5], c.1210-12T[7], c.1210-12T[9] (T5, T7, T9) in the intron 8 of CFTR gene in normal individuals and cystic fibrosis patients in the north of Iran.
Material and methods: 40 CF patients and 40 normal individuals were screened for poly T polymorphism in intron 8 of CFTR gene using Reverse Dot Blot method which was also used to detect p.Phe508del among CF patients.
Results: T7 allele is the most prevalent in both normal and CF patients. Its abundance is approximately 75%. T9 and T5 represent approximately 20% and 5% of alleles respectively. T7/ T7 genotype is the most present in both normal and CF patients with 72.5% and 60% prevalence respectively. p.Phe508del was present in 13 CFTR alleles belonging to 7 patients with either homozygote T9/ T9, T7/ T7 or compound heterozygote T7/ T9 genotypes.
Conclusion: Contrary to the Caucasians, T7 allele is more frequent in Northern Iranian CF patients. The presence of p.Phe508del and T7 allele in the same framework is reported for the first time in this part of the world. Further investigations of other populations will help to understand whether p.Phe508del arose by selection pressure in this part of the world or was imported from European countries. The abundance of T5, T7, T9 alleles indicates that this polymorphism can be used as one of the informative markers for detection of normal and mutant alleles in prenatal diagnosis or carrier assessment in families with previous history of the disease in regions with high degree of CFTR mutation heterogeneity. 相似文献
997.
998.
Fereydoun DAVATCHI Mahmood AKBARIAN Farhad SHAHRAM Abdolhadi NADJI Farhad GHARIBDOOST Ahmad‐Reza JAMSHIDI 《International journal of rheumatic diseases》2006,9(1):60-63
Aim: To evaluate the overall effect of disease modifying anti‐rheumatic drug (DMARD) combination therapy in daily practice. Methods: In a retrospective study, 161 consecutive files of patients who attended regular follow‐up sessions, seen from 1998, were analysed. Their data were extracted at baseline, 6 months, 1, 2, 3, 4 and 5 years. American College of Rheumatology ACR70 criteria was chosen for the evaluation of the global result. DMARD combination was methotrexate (7.5–15 mg weekly) and chloroquine (150 mg daily), with low‐dose prednisolone (less than 10 mg daily). In cases of remission, methotrexate was gradually tapered, then prednisolone. Chloroquine was discontinued after 1 year if no recurrence occurred at low‐dose (150 mg every other day). In cases of recurrence at any stage, the treatment scheme was stepped back. Results: The data of 161 patients were analysed. One hundred and six were rheumatoid factor positive (RF+) (66%). ACR 70 for all patients at 6 months follow‐up was 72.5% (95% CI = 7.0); at 1 year, 75.8% (95% CI = 6.7); at 2 years, 72.2% (95% CI = 7.2); at 3 years, 78.9% (95% CI = 6.6); at 4 years, 78.4% (95% CI = 6.9); and at 5 years, 70.6% (95% CI = 8.5). Conclusion: The classical DMARD combination therapy, when used with adequate low‐dose prednisolone, gave an ACR70 response from 71–79%. The efficacy of the treatment did not fade over time. RF– patients did better than RF+ patients, but the difference was not statistically significant. 相似文献
999.
Toufic Elbeaino Hulusi Kiyi Reza Boutarfa Angelantonio Minafra Giovanni Paolo Martelli Michele Digiaro 《Archives of virology》2014,159(10):2757-2764
The RNA2 of seven grapevine fanleaf virus (GFLV) isolates from vines with yellow mosaic (YM) symptoms from different origin were sequenced. These sequences showed a high variability in the homing protein (2AHP) and, in five of them, a putative recombination with arabis mosaic virus (ArMV) was detected. To investigate recombination frequency, the partial sequences of the 2AHP of 28 additional GFLV isolates from nine different countries, showing either YM or infectious malformations (MF) symptoms, were obtained and compared with those of GFLV isolates from GenBank. The analysis confirmed the high level of sequence variability (up to 41 % at the nucleotide level) among isolates. In phylogenetic trees constructed using different approaches, the sequenced isolates always clustered in four conserved groups, three of which comprised YM strains (groups 1, 2 and 3), and one (group 4) the MF strains. Potential interspecific recombination sites between GFLV and ArMV were predicted in the 2AHP gene of several isolates, all of which were associated with YM symptoms. 相似文献
1000.
Inagaki T Begum T Reza F Horibe S Inaba M Yoshimura Y Komatsu Y 《Neuroscience research》2008,61(2):192-200
High-frequency stimulation (HFS) induces long-term potentiation (LTP) at inhibitory synapses of layer 5 pyramidal neurons in developing rat visual cortex. This LTP requires postsynaptic Ca2+ rise for induction, while the maintenance mechanism is present at the presynaptic site, suggesting presynaptic LTP expression and the necessity of retrograde signaling. We investigated whether the supposed signal is mediated by brain-derived neurotrophic factor (BDNF), which is expressed in pyramidal neurons but not inhibitory interneurons. LTP did not occur when HFS was applied in the presence of the Trk receptor tyrosine kinase inhibitor K252a in the perfusion medium. HFS produced LTP when bath application of K252a was started after HFS or when K252a was loaded into postsynaptic cells. LTP did not occur in the presence of TrkB-IgG scavenging BDNF or function-blocking anti-BDNF antibody in the medium. In cells loaded with the Ca2+ chelator BAPTA, the addition of BDNF to the medium enabled HFS to induce LTP without affecting baseline synaptic transmission. These results suggest that BDNF released from postsynaptic cells activates presynaptic TrkB, leading to LTP. Because BDNF, expressed activity dependently, regulates the maturation of cortical inhibition, inhibitory LTP may contribute to this developmental process, and hence experience-dependent functional maturation of visual cortex. 相似文献